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Download TX System RISC TX79 Core Architecture (Symmetric 2
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Appendix D COP1 (FPU) Instruction Set Details ROUND.L.fmt 31 ROUND.L.fmt Floating Point Round to Long FixedPoint 21 20 16 15 11 10 6 5 26 25 0 COP1 010001 fmt 0 00000 fs fd ROUND.L 001000 6 5 5 5 5 6 MIPS III ROUND.L.S fd, fs Format: ROUND.L.D fd, fs Purpose: To convert an FP value to 64-bit fixed-point, round to nearest. Description: fd ← convert_and_round (fs) The value in FPR fs in format fmt, is converted to a value in 64-bit long fixed-point format rounding to nearest/even (rounding mode 0). The result is placed in FPR fd. When the source value is Infinity, NaN, or rounds to an integer outside the range -263 to 263 -1, the result cannot be represented correctly and an IEEE Invalid Operation condition exists. The Invalid Operation flag is set in the FCR31. If the Invalid Operation enable bit is set in the FCR31, no result is written to fd and an Invalid Operation exception is taken immediately. Otherwise, the default result, 263 –1, is written to fd. Restrictions: The field fs and fd must specify valid FPRs; fs for type fmt and fd for long fixed point; see Floating-Point Resisters on page 10-2. If they are not valid, the result is undefined. Operation: StoreFPR (fd, L, ConvertFmt (ValueFPR (fs, fmt), fmt,L) Exceptions: Coprocessor Unusable Reserved Instruction Floating-Point Inexact Unimplemented Operation Overflow Invalid Operation D-32
